Until Fulltone's OCD (Obsessive Compulsive Drive), pedals just couldn't hold up to what a high quality amp could do. You lose all the touch sensitivity and you can forget about those complex Harmonics. It's always been somewhat of a compromise using Overdrive pedals until now. The OCD is designed to replicate the dynamics and harmonic structure of an overdriven tube amp, it uses a unique multi-stage distortion circuit, as opposed to the more common diodes-in-feedback-loop/diodes-to-ground configurations. The designers at Fulltone made this pedal for themselves, but they'll let you use it too. And you'll love it!
If you've ever owned a GREAT amp, like a Marshall 18 watt, a VOX AC15, a Marshall JTM45 and if you have a place where you can crank them up loud, then you know what we're talking about. Smack a power chord and you (not only) hear the fundamental notes...but you get (count 'em) 4, 5, even 6 additional overtones ringing into a feedback... notes that you can whistle if your ear is good enough! Think; Led Zeppelin's Ocean, Custard Pie, Classic tones including James Gang, the Beatles, AC/DC, FREE., etc.
Back off the guitar's volume and there are a dozen great other sounds at your fingertips... Clean, spanky sounds, with all the highs and lows still intact. And a Tele still sounds like a Tele, a Les Paul like a Les Paul.
Frequently asked questions about Fulltone's OCD:
Q:The OCD has the brightest LED I've ever seen, it lights up my entire pedalboard, but there is NO POPPING sound like on my other booteek effects...is the OCD true bypass?
A: Yes it is true bypass, and thanks for noticing the no pop thing. Fulltone's designer invented an active anti-pop circuit (not simply resistors to ground ;) that eliminates almost all the snap, thump, and pop you're used to getting at higher volumes with true bypass pedals.
Q:The OCD is huge sounding, wide open sounding, why does it make my other Overdrives sound like there's a blanket over the speakers in comparison?
A: Because 99% of all pedals use clipping diodes to achieve their distortion, and the net result is you are lopping off the upper frequencies (harmonics) and most of the lower frequencies, leaving mostly only Midrange.
Q:You're right, but why don't I hear it with other overdrives?
A: Because your overdrives filter out (Lop off ) the upper harmonics, the upper frequencies, and mask your amp's fizziness. Just turn down the OCD's Tone control, which only affects those upper frequencies....or better yet, fix the amp.
Q:Is it ok to run the OCD higher than 9 volts?
A: Yes, you can run 9volts DC, 12volts DC, up to 18 volts DC, just make sure that the Center Pin of the adapter is Negative. BTW, you can't hurt the OCD by using the wrong adapter because it has special protective circuitry...if you use the wrong adapter it just won't work or it will hum, but you can't hurt it.